The present invention relates to roller bottles for cell growth and production, and more particularly concerns a device having a greatly increased internal surface area of the roller bottle in order to achieve enhanced quantities of cells grown from a single roller bottle. The invention includes the utilization of a liner or a sleeve comprised of a foamed, woven or textured material. Also, the material may be microporous. Thus, the interstices or minute openings and surfaces formed in the texture, weave or foam of the sleeve or liner has the effect of increasing substantially the effective surface area on the internal surface of each roller bottle. For this reason, the invention provides a cost effective approach to the greatly increased number of roller bottles being utilized for cell growth.
The invention includes the utilization of the foamed microporous textured or woven sleeve of the invention in a single use roller bottle. With such an arrangement, the sleeve is inserted prior to the final welding or joining of the parts forming the roller bottle together. Alternatively, a reusable roller bottle may be utilized which may be opened for insertion of a sleeve of the invention sequentially for each use of the bottle. With such an arrangement, once the cells are harvested from a culturing stage in the use of the roller bottle, the sleeve is removed and discarded, and the roller bottle sterilized for subsequent use. After sterilization, of course, a new liner or sleeve is inserted for the additional use.
Containers which are used in the laboratory and like situations for culturing of cells are commonly known as "roller bottles." These roller bottles are generally cylindrically shaped and are adapted to rotate about their axes. The internal surfaces of such roller bottles are for providing active surfaces for the growth of cells. A liquid growth medium is introduced into the roller bottles. The rotating movement of the bottle keeps the internal surfaces wetted with the liquid medium, thereby encouraging the growth of cells. Rotating rollers in an appropriate apparatus are employed to rotate these roller bottles. Usually, the roller bottle apparatus, as is described below, is adapted to be placed inside an incubator or incubating room to control the temperature of cell growth inside the roller bottles.
As will be understood by practitioners-in-the-art, it is desirable to grow large amounts of cells, mostly for cell by-products, such as pharmaceutical substances that are secreted by cells; for example, insulin, interferon, urokinase or viral vaccines. The standard roller bottles have been successful in increasing the yield of cell growth in as much as the entire inside peripheral surface can be utilized for cell culturing.
In conceiving ways to increase the yield of growing cells in roller bottles, there are substantial constraints which have to be considered in suggesting improvements. In particular, roller bottle rotation devices are widely used in standard sizes and incubators. These devices are in place in many laboratories and are designed to accept roller bottles of a specific size and shape. Thus, to replace these would be expensive and cause substantial lack of standardization throughout the laboratory field.
The outside configuration or diameter of roller bottles is generally not one of the parameters which has changed to improve the yield of cells grown in roller bottles. Accordingly, improvements in roller bottles for increasing cell growth, for practical purposes, is limited to modifications of interior surfaces of the roller bottles, and/or improvements in harvesting the cells once they are grown.
One of the problems of the approaches which have taken place in the past has to do with the fact that involved mechanical improvements to roller bottles increase the cost thereof. Literally, thousands of roller bottles are used on a daily basis and are discarded, once they are used. Therefore, the cost of roller bottles must be decreased because of the vast increase in equipment and development costs for medical applications.
Various approaches have been used in order to increase the surface area internally of roller bottles. One approach is to increase the amount of actual surface available for cells to grow on. Representative prior art devices which increase the surface area internally of conventional roller bottles are U.S. Pat. No. 3,941,661, issued Mar. 2, 1976; U.S. Pat. No. 4,317,886, issued Mar. 2, 1982; and co-pending U.S. Application Ser. No. 204,796 filed June 10, 1988.
Another approach to increase the yield of cells developed internally of roller bottles includes the combination of increasing the surface area thereof, and the use of involved mechanical devices cooperating with these increased surfaces in order to remove a greater harvest of cells once they are developed on the increased surface internally of the bottles. Representative of these devices include those taught and claimed in U.S. Pat. No. 4,004,981 issued Jan. 25, 1987; U.S. Pat. No. 4,065,359 issued Dec. 27, 1977; and U S. Pat. No. 4,600,694 issued July 15, 1986.
While each of the above three patents have the effect of increasing the surface area internally of roller bottles and increasing the yield of cells removed therefrom, the internal device utilized in these patents in the arrangements for scraping the cells from the increased surface areas are very involved, and increase the cost of the individual roller bottles, and the product derived therefrom, substantially. Moreover, these are not single-use devices and have been used largely in the labs where they originated.
With this invention, by contrast, a device is provided for roller bottles which is inserted into the roller bottles in tee form of a liner or sleeve which increases the actual surface area useful for cell growth thereon. The sleeve or liner is comprised of a foamed, textured or woven material which provides minute surfaces surrounding the interstices forming the texture, weave and/or foamed characteristics of the sleeve or liner of the invention.
Because of this, the actual surfaces involved for cell growth include areas positioned at planes diverging from the general plane of the liner or sleeve of the invention. For this reason, each roller bottle has a substantial increase in cell growth production area or surface for each use of the bottle.
The invention contemplates, as one embodiment, the use of the sleeve or liner of the invention in a single-use roller bottle. That is, the sleeve or liner is inserted into the formed bottle prior to the top or cap of the roller bottle being welded into place on the cylindrical body portion of the roller bottle. Thus, the roller bottle is used a single time, cells are grown on the surfaces thereof, and the cells are thereafter removed and the roller bottle thrown away.
Alternatively, the sleeve or liner of the invention may be used in a multiple or repeat use roller bottle. That is, the roller bottle may have one or both ends screwed onto or otherwise removably attached to the cylindrical body portion of the roller bottle. This provides access to the internal area of the roller bottle for repeat insertion of one of the liners or sleeves of the invention. Thus, once the roller bottle is used, and cells are developed or cultured on the internal surface of the roller bottle on the interstices and uneven areas of the liner of the invention, the cells are harvested and the top or bottom or both are removed from the used roller bottle and the used liner is removed and discarded. Thereafter, the parts forming the roller bottle are sterilized and a new liner is inserted for subsequent use of the same roller bottle.
In viewing generally the conditions for producing roller bottles in accordance with this invention, a variety of thermoplastic materials may be utilized, including, for example, polystyrene, polyethylene terephthalate, the polyolefins, polyurethane and polyvinyl chloride. These materials are representative of materials which would be utilized for the single-use form of roller bottle utilizing the sleeve or liner of the invention here. Such a single-use roller bottle may be blow molded, as will be understood by practitioners-in-the-art, which reduces the cost of the individual roller bottles produced in accordance herewith.
Alternatively, if a reusable roller bottle is to be formed in accordance with this invention, the materials selected for such repeat use must be comprised of a material which will tolerate repeated sterilization procedures. Materials which may be used include, for example, glass, stainless steel or certain resins which tolerate the conditions necessary for sterilization. Of course, reusable bottles allow considerable cost savings to the end user, because the disposable inserts of the invention are cheaper than the cost of purchasing a new roller bottle.
The inserts of the invention may be made from a variety of materials which improve cell growth surface area. Polyethylene terephthalate, polyurethane and certain papers having the appearance or property of "woven" characteristics may be utilized for the inserts. Whereas these materials were not desirable in the past because of their poor structural properties in a foamed, woven, microporous or textured format, by utilizing them as liners or sleeves in a separate roller bottle provides the support required for these materials which are, otherwise, desirable for cell growth surfaces.
Representative specific materials which may be used for the sleeves or liners of the invention include microporous materials such as polypropylene, ultrahigh molecular weight polyethylene, high density polyethylene and styrene arrylonitrile, all of which may be obtained from either Porex Technologies, 500 Bohannon Road, Fairburn, Ga. 30213, or Chromex Corporation, 19 Clay Street, Brooklyn, N.Y. 11222. A further representative material is foamed polyurethaneether which may be obtained from W. R. Grace, Organic Chemical Division, 55 Hayden Avenue, Lexington, Mass. 02173.
As further exemplary of materials which may comprise the sleeve or liner of the invention is textured or woven paper such as 40 pound basis weight medical grade paper supplied by James River Corporation, 100 Island Avenue, Parchment, Mich. 49004-1391 or 42 pound basis weight medical grade paper supplied by CPM Incorporated, P.0. Box 1280, 131 Sullivan Street, Claremont, N.H. 03743.
In addition, non-woven fabrics or composites may be used such as spun-bonded polyester which may be obtained from Eaton-Dikeman, P.0. Box A, Mount Holly Springs, Pa. 17065-0238.
Other objects and advantages of this invention will be apparent from the following description, the accompanying drawings and the appended claims.